The application control technology, such as the Java™ programming, for virtual machines has been widespread in the personal computer software industry. Currently, how the Java (Registered Trademark, hereinafter™) programming, as a development from personal computer software, can be used to achieve playback control in BD-ROM (Blu-ray Disc Read Only Memory) playback apparatuses is studied eagerly.
As a conventional technology in regards with a similar playback apparatus, the technology recited in the following Patent Document 1 is known.    *Patent Document 1: Japanese Patent Publication No 2813245